Automatic phonograph



March 6, 1951 i F. M. JOHNSON AUTOMATIC PHONOGRAPH 8 Sheets-Sheet 1Filed Nov. 5, 1945 ,4 T TQIQNEY March 6, 1951 F, sd 2,544,230

AUTOMATIC PHONQGRAPH Filed Nov. 5, 1945 8 Sheets-Sheet 2 INVEN TOR.QqA/K J el-v 50M March 6, 1951 F. M. JOHNSON AUTOMATIC PHONOGRAPH 8Sheets-Sheet 3 Filed Nov. 5, 1945 kffismwvf I N VEN TOR. FEHNK JOHN 501vB Y A TTOENE Y March 6, 1951 F. M. JOHNSON AUTOMATIC PHONOGRAPH 8Sheets-Sheet 4 Filed Nov. 5, 1945 INVENTOR.

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k N wm ,4 T TOIQ/VEY Filed Nov. 5, 1945 8 Sheets-Sheet 5 March 1951 i F.M. JOHNSON 2,544,230

AUTOMATIC PHONOGRAPH 4 INVENTOR. FRHNK H/vso1v 8 Sheets-Sheet e F. M.JOHNSON AUTOMATIC PHONOGRAPH March 6, 1951 Filed Nov. 5, 1945 UQ MFQQQNMarch 6, 1951 JOHNSON 2,544,230

AUTOMATIC PHONOGRAPH Filed Nov. 5, 1945 8 Sheets-Sheet 7 INVENTOR. WWVKM H/vso- March 6, 1951 F. M. JOHNSON AUTOMATIC PHONOGRAPH 8 Sheets-Sheet8 Filed Nov, 5, 1945 A TTO/ZNEY Patented Mar. 6, 1.951

UNITED STATES PATENT OFFICE AUTOMATIC PHONOGRAPH.

Frank M. Johnson, New York, N'. Y., assignor to Universal CameraCorporation, New York, N. Y., a corporation of Delaware ApplicationNovember 5, 1945,. Serial No. 626,732

cause the least possible strain and shock to the records.

It is a further object of this invention to providein a phonograph ofthe character described a mechanism which effects a quicker change fromone record tothe succeeding record than is attained by other mechanismsof this general type whereby to enhance the effect of continuity in theplaying of records.

It is an additional object of this invention to provide in a phonographof the character described a mechanism which will detect the end of arecord positively, accurately, and with a minimum time delay.

Still another object of this invention is to eliminate the error indetecting the end of a record, which error is due to the eccentricity ofthe record spiral with respect to the center of rotation of theturntable.

Still a further object of this invention is to provide a phonograph ofthe character described, the elements of which are so constructed andarranged that the phonograph is durable and eflicient in operation andcomprises. relatively few and simple parts which can be fabricated andassembled economically.

Other objects of this invention will in part be obvious and in parthereinafter pointed out.

The invention accordingly consists in the features of construction,combinations of elements and arrangement of parts which will beexemplified in the construction, hereinafter described, and of which thescope of application will be indicated in the appended claims.

Certain features of the invention herein shown and described, but notclaimed, are shown, described andclaimed in my co-pending applicationSerial No. 590,202, filed April. 25,, 1945..

In the accompanying drawings in which is shown one of the variouspossible embodiments of my invention,

Fig. 1 is a vertical sectional view through a phonograph embodying theinvention, the same being taken substantially along a plane runningthrough the centers of rotation of the turntable and the tone arm;

Fig. 1a and lb are schematic views showing various positions of theoperative parts of the mechanism for transferring a record from thestack to the turntable;

Fig. 1c is a fragmentary top view of the phonograph showing the stackleveler in playing position;

Fig. 2 is a vertical sectional view through said phonograph takensubstantially along a plane at right angles to Fig. 1 and runningthrough the center of rotation of the tone arm;

Fig. 3 is a fragmentary auxiliary sectional view of the mechanism fordetermining the end of a record and starting the record changing andtone arm moving cycles;

Figs. 3a, 3b, 3c and 3d are schematic views showing various positions ofthe operative parts of the mechanism for determining the end of arecord;

Figs. 4, 5, 6 and 7 are schematic views showing various positions of theoperative parts of the discriminating mechanism for setting the tone armin the starting, grooves of records of different fixed diameters;

Figs. 8 and 8a are enlarged, sectional views taken substantially alongthe line 83 of Fig. 1 and showing various positions of certain operativeparts of the discriminating mechanism and of the mechanism fordetermining the end of a. record;

Fig. 9 is an enlarged fragmentary top plan view taken substantially onthe line 9-9 of Fig. 1 and showing the driving and timing means for therecord changing and tone arm moving mechanisms; and

Fig. 10 is an enlarged sectional View taken substantially, along theline Iii-l0 of Fig. 1 and showing the driving means for the recordtransferring mechanism.

Referring now to the drawings, there is illustrated a phonographembodying the invention andcomprising a turntable l secured to a hub 2which is mounted forrotation about a stationary central post 3 and isseated on a thrust bearing 4. The turntable. is driven by conventionalmeans, such for example as an electric motor 5 which, through a suitablereduction train, turns a disc 5A covered with friction material, forinstance rubber, which engages the inside of the. downturned peripheralrim of the turntable, thus providing a frictional. rim, drive.

The record magazine of a commercial record disc, so that it can beslidingly received therein. At its upper end the central post has aninset step 3A cut therein. Said upper end, further, is provided with anerect cylindrical extension 33 whose axis is ofiset from the axis of thepost 3. The diameter of the extension is considerably less than that ofthe post, being sufiiciently small to be rotatably received in theinternal longitudinal offset bore of a cylindrical cap 6. Said cap has adiameter the same as that of the central post, so that it may be turnedabout the cylindrical extension 33 to a position in which the axis ofthe cap is coincident with the axis of the post. The eccentricity oroffset of the axis of the projection 3B and that of the cap 6 is suchthat when the cap is turned 180 away from the position in which the axisof the cap is aligned with the axis of the post, a portion of thesurface of the cap will be approximately in registration with the riserof the inset step 3A at the top of the central post. The height of saidriser is slightly greater than the thickness of a commercial record atits center, but is less than the thickness of two records at theircenters. Free rotation of the cap 6 is limited between these twopositions by a pin I mounted on the reduced cylindrical extension 3B andmating with a slot in the cap.

When it is desired to load records in the magazine, the cap 6 is rotatedto align a portion of its surface with the riser of the step 3A. Nowrecords can be deposited on the cap and these records will descend nofurther than the tread of the step. After records have been played, thecentral cap 6 is rotated 180 to the position in which it is coincidentwith the central post. Now there is no bend, overhang, step orprojection to prevent a straight lift in the removal of the playedrecords.

The mechanism for leveling records in the stack The stackrecord-leveling mechanism consists of a main arm 8 rotatably secured bya pivot SA on a bracket I fixed to the phonograph support S. Said armextend beyond the central post 3, and. the free end thereof rests on thetop surface of the top record in the stack. The main arm has a slot 83in which there is freely received the central post 3 whereby said mainarm is diametrically located with respect to the records in the stack.Said leveling mechanism also includes a secondary arm 9 aligned with andpivotally mounted on the main arm 8 at a point between the central postand the bracket ll]. One end of the secondary arm rests upon the top ofthe central post cap 6, and at its pivot point the secondary arm isresiliently urged upwardly by means of a biasing leaf spring 9A. Thelengths of the two arms and the positions of their pivotal mountingpoints are so proportioned that the bottom ends of both arms are alwaysat substantially the same horizontal level. In this manner, the main arm8 urges the records down on one side of the central post until thesecondary arm 9 contacts the record stack to prevent further downwardmovement of the main arm, thus maintaining the record stack level. Inthe illustrated embodiment of the invention, such proportioning isattained by pivoting the secondary arm midway between the pivot point 8Aand the free end of the main arm, and by having the pivoting point ofthe secondary arm midway between the central post 3 and the bottom endof the secondary arm.

The mounting bracket ID has a loading blade l2 fixed to its base, andsaid bracket is pivoted on a 'screw l3 which is fixed to a pedestalsecured to the phonograph support S. The loading blade extends at anangle of about to the main record leveling arm 8, so that when said armis in position to level the records in a stack, the record loading bladeI2 is clear of the largest diameter disc which the phonograph is adaptedto play. Such position of said blade is shown in Fig. 1c. The loadingblade is long enough to support the smallest diameter record which thephonograph is adapted to play at such time as said loading disc is inoperative position.

When a set of records is to be placed into position vertically spacedabove the turntable, the leveling arm is raised and rotated 90 clockwisefrom the position shown in Fig. 10. This causes the loading blade I2 toproject towards the central post, said blade then occupying the positionindicated by the dot and dash lines in this figure. At such time whenrecords are loaded on the cap 6 (which has been rotated to eccentricposition), the lowermost record will be supported at its center on thestep 3A and adjacent its periphery on the loading blade l2. After allthe records to be played have been placed on the cap 6, the operatorplaces his hand upon the top record and holds the stack of recordslevel. Now the leveling or the main arm 8 is swung counter-clockwise aquarter of a turn to swing the loading blade l2 out of the way and placethe leveling arm in proper angular position for operation. Then theleveling arm is swung downwardly about pivot 8A until the center postcap 6 is received in the slot 8B. The main and secondary arms are thenallowed to fall until the two arms press down in a common horizontalplane on the top of the uppermost record in the stack. The main arm 8 isresiliently urged downwardly by means of a helical tension sprin I I.

The cycling mechanism To start the operation of the record-loweringmechanism, a reject button I4 is pressed. This button is slidablymounted on the phonograph support S and is biased outwardly by a springI5.

'= Pressing said button shifts a slide bar [6 whose forward end has adepending finger. In the advanced position of said lever, this fingerengages the lower end of another lever I! which is rotatably mounted bya pivot IS on a cycle disc 20. Advance of the lever l6 turns the leverI! about its pivot in a counter-clockwise direction, as viewed from Fig.2, causing the upper end of the lever to project a substantial distanceabove the cycle disc. The position assumed by the lever I1, when movedby pressing of the reject button I4, is illustrated in Fig. 3d. Thecycle disc 20 is secured for rotation to a cycle shaft 28 which isjournaled in a pair of bearings 29, 30 mounted on brackets 3|, 32 whichare dependent from the support S. Said cycle disc has a peripheral notch20A which, in normal position of the phonograph, i. e. during playing ofa record, is uppermost. The axis of revolution of the cycle discintersects the axis of revolution of the central post 3, and

' said notch is so disposed that in normal position of the phonographthe same i registered with the hub 2 of the turntable. Said hub has afriction element, such as a rubber tire 2 I, carried thereon, the tirebeing of a diameter sufliciently large to cause the same to project intothe notch 29A of the cycle disc. Thus when the phonograph is played,said tire will rotate freely, even though a portion of the same extendswithin the plane of cycle disc (as is seen in Fig. 9). The hub 2 has apin {9 (Figs. 1, 3, 3a, 3b, 3c and 3d) amazes on its undersurface,having a vertical side wall which, during travel of the pin with theturntablawill traverse the position occupied bythe raised upper end ofthe lever I! when said lever is in the position illustrated in Fig. 3d,this position being that which the lever is caused to assume uponoperation of the reject button [4. When the vertical side wall of thepin [9 engages the raised upper end of the lever I I, there will firstbe a tendency to turn said lever about the pivot W. This motion,however, cannotbe obtained because the lower end of the lever restsagainst a stop WA on the cycle disc. Consequently, engagement of thelever I! by the pin l 9 causes the cycle disc to rotate in acounterclockwise direction, as viewed in Figs. 3a and 3d. The upper endof the lever I I and the vertical side wall of the pin iii are sodesigned that they will remain in engagement until the cycle disc hasbeen angularly turned at least a distance sufficient to cause the rubbertire 2| to engage the unbroken surface of the cycle disc. After suchtime the rubber tire will drive the cycle disc until the notch 20A isagain reached. In the foregoing respect the cycle disc may be consideredas a one-revolution clutch. Revolution of said cycle disc drives thevarious operating mechanisms, hereinafter described, in proper timedrelationship. It may be mentioned at this time that the cyclingmechanism comprising the cycl ng disc is driven from and by theturntable, andthis construction in general obtains a very rapid cycleand employs an extremely small number of parts.

The record-lowering mechanism The cycling disc has a pin 22 (Figs. 1 andsecured to the same for rotation therewith. This pin has a reducedportion thereof slidably received in a slot in a flat lever 23 which ispivotally mounted on a bracket 24 pendant from the support S. The lever23 includes a second slot in which there is slidably received a secondpin 23A which is fixed in a selector slide 25. As the pin 22 rotateswith the cycle disc, it causes the lever 23 to oscillate about itspivotal mounting point on the bracket 24, and as this lever oscillates,it moves the selector slide 25 up and down. Said slide is constrainedfor vertical movement by mounting on the central post 3. The sl decarries an elongated non-circular selector rod 26 which rides in agroove 26A of matching contour in the central post 3. Thus it will beseen that as the cycling disc rotates, it causes the rod 26 tovertically reciprocate. A selector dog 21 is pivoted on top of theselector rod 25' and moves up and down with said rod. Said dog isslender enough to fit entirely within the groove 26A. In addition, theright-hand side of the dog (as viewed in Fig. l) is rounded and isadapted to engage the cammed upper end 263 of the groove 26A when saiddog is in its uppermost position, for a purpose which will be explainedhereinafter. Finally, the left-hand side of the dog (likewise as viewedin Fig. 1) has a step 21A formed therein. This causes the tip of the dogto be pointed. The dog operates as follows: Assume the uppermost recordon the turntable has just finished playing. The cycle disc starts toturn. At this instant the selector rod 26 is in its lowermost positionwith the dog 21 disposed below the level of the turntable. Rotation ofthe cycle disc initially causes the rod and dog 2'! to rise, The dog maybe pivotally mounted in such manner that at this time the center ofgravity of the dog is to the right of the pivotal mounting whereby thedog will naturally stay in anerect position as it is elevated. When thedog nears its uppermost position, its

- tip will already have been projected into the center aperture of thelowermost record in the stack. Engagement of the right-hand side of thedog with the cammed surface ZEB now tips the dog over to the left,causing the riser of the step 21A to engage the inside of the hole inthe record. Further upward movement of the dog presses the dog more tothe left and causes the lowermost record in the stack to be shifted tothe left. The dog and its step are so proportioned that the record willbe shifted to the left, enough to align its central hole with the axisof the central post 3. When the record is in this position, the tip ofthe dog will project beyond the groove 26A, such position beingillustrated in Fig. la. At this time the cycle disc is rotatedapproximately and further rotation of the disc will cause the dog todescend. As the dog descends, the lowermost record will come down withit, said record being centrally supported on the step 21A (see Fig. lb)so that said record does not experience a free fall, but rather has acontrolled drop and thus prevents clatter, breakage or chipping of therecord. As the dog re-enters the central hole in the hub 2, it will bestraightened out and once more forced back into its idling position asshown in Fig. 1. Thus the dog is repositioned and ready to operate onthe next cycle for the lowering of another record from the stack to theturntable.

The tone arm positioning mechanism From the time that the playing of onerecord is finished to the time that the succeeding record is started,the tone arm must rise from the played record, be swung clear of adescending re ord regardless of its diameter, return to a position overthe starting groove of the lowered record, and. then lowered to engagethe needle into the starting groove of the said record, regardless ofits size. Pursuant to a feature of the invention, the automaticphonograph is capable of playing re"ords of a plurality of predeterminedbut different diameters. Basically, said phonograph may be construct dto play records of any number of different fixed diameters. However, inthe embodimmt of the invention illustrated herein, the phonograph isshown as being adapted to play records of only two different diameters,it being understood. that the phonograph may be modified in accordancewith the underlying principle described herein to accommodate records ofa greater number of different fixed diameters. In general, the tone armis conditioned to be set in the starting grooves of records of differentfixed diameters by means of a detector mechanism hereinafter describedin detail. This detector system does not operate when records of thesmaller size are played and functions only to control the position ofthe tone arm upon the playing of records of the large size. Accordingly,the tone arm positioning mechanism will be discussed without thedetector system at the present time in order to explain its generalconstruction and operation. Rotation of the cycle disc 28 causesrotation of the cycle shaft 28 which, as has already been mentioned, issecured at one end thereof to the cycle disc. Affixed to the oppositeend of the cycle shaft is a lift cam 33 (Figs. 1 and 2) which engages alift pin 34. This pin is mounted for free vertical movement and for freerotation about a vertical axis. Movement of the pin is otherwiseconstrained. At its upper end the pin 34 is pivotally fixed. to the tonearm T in such manner that said pin will rotate about its vertical axiswith movement of the tone arm about the same axis, and that the pin willmove vertically upward and downward with the rotation of the tone armabout a horizontal axis. At the rear of the tone arm is a shelf 35. Aroller 36 is rotatably mounted on a bracket 31 fixed to the support S.Said shelf and roller limit the rise of the rear of the tone arm. As thelift cam 33 rotates with the cycle disc, the lift pin 34 is elevated,causing the engagement of the shelf 35 with the roller 36. Continuedrise of the lift pin causes the tone arm to rotate about a horizontalaxis in a clockwise direction, as viewed from Fig. 1, thus lifting theneedle N clear of the played records. The amount of lift can be adjustedby varying the height of the bracket 21. This height of the tone arm ismaintained by proper shaping of the cam 33 until near the end of thecycle when the pin 34 engages the depressed surface of the cam 33 andcauses lowering of the pin, and hence lowering of the needle.

Horizontal rotation of the tone arm is caused by cam 38 (Figs. 1, 2, 8and 8a) which acts against a follower 39 fixed to the lift pin 34 formovement therewith. The follower 39 is so shaped that it is notcontacted by cam 38 until the tone arm is fully raised. Upon contact,the cam 38 then drives the follower 39 back, causing the tone arm torotate outwardly away from the central post 3 to a position clear of adescending record of the largest diameter. At such time the cam engagesa curved portion of constant diameter in the follower 39, so that thetone arm will remain stationary, the follower being so shaped that saidtone arm will not commence to move inwardly until the record beinglowered by the dog 2! has reached a position lower than the tone armneedle. The portion of the follower 39 which is engaged by the cam 38 tomove the tone arm inwardly constitutes a return spring 49 (Figs. 2, 8,and 811). When said cam engages the spring, thefollower 39 will berotated in a clockwise direction, as viewed in Fig. 8, moving the tonearm toward the central post 3. In order to dispose the same in thestarting groove of the record just lowered, the follower 39 rotates insuch direction until a shoulder 39A thereon abuts against a stop,hereinafter more fully described with reference to the discriminator ordetector mechanism. This stop halts inward movement of the tone arm whenthe same is above the starting groove of the next record to be played.However, the cam 33 continues to rotate, and it is for this reason thatthe follower portion 49 is made resilient. The cam deflects the followerspring portion 49 until said portion disengages from the cam.

It may be mentioned that this engagement between the spring 49 and thecam 38 should 'be complete before lowering of the lift pin 34 moves theprojection 39A away from the stop which has halted its movement. Thispermits the needle to be lowered to a predetermined position in thestarting groove of a record of any fixed diameter. In the idlingposition of the cycling mechanism, as shown in Fig. 2, the lift pin isfully depressed and the tone arm released from all control, the latterrotating freely on the lift pin which rests on the lift cam 33. Anyrotation of the tone arm about a horizontal axis during its playingposition will be about the top of said pin, since in playing position,the roller 38 is clear of the shelf 35.

The mechanism for determining the end of a record When the cycle disc 20has completed one revolution and the rubber tire 2| re-entered the notch20A, the needle will be disposed in the starting groove and theturntable will continue to rotate, causing the last lowered record toplay. The needle will follow the recorded groove until the end of playwhereupon it will enter the leadoff groove. A play end sensing mechanismmust then cause the cycling mechanism to start its operation. The playend sensing mechanism includes a long, rigid strip 42 (Figs. 1, 2, 3, 8and 8a) which is mounted at one end for pivotal rotation about the liftpin 34. A horizontal plate 39B movable with the follower 39 underliesthe pivotally supported end of the strip 42, and said strip extends farbeyond the edge of said plate. A collar 34A is secured to the lift pin34 a short distance above the plate 39B. With this construction, theweight of the strip 42 is carried by the extended edge of the plate 393about which said pin fulcrums, the pivotally mounted end of the stripengaging the under side of the collar 34A, as best seen in Fig. 3. Suchconstruction wil1 cause a frictional engagement between the strip 42 andthe system which moves with the follower 39, said system including thecollar 34A and the plate 393.

Due to the foregoing frictional engagement, the strip 42 will rotateabout the lift pin 34 together with the follower 39 unless thefrictional engagement between said strip and the system moving with thefollower 39 is overcome. In such case, of course, the strip will rotatewith respect to the fol'ower 39 in the direction of the applied force.The normal position of the strip 42 with respect to the system of thefollower 39 is shown in Figs. 8 and 8a. In such position, said striprests against a stop 44 carried by the plate 393. The strip is caused toassume such a position during an outward sweep of the tone arm by a pin43. Thus, the strip is reset every time that the tone arm movesoutwardly subsequent to the playing of one record and prior to theplaying of the following record. In this reset or normal position, thestrip 42 occupies a predetermined angular position relative to the tonearm which is such that as the tone arm moves inwardly during theplayingof a record, the tip of the strip 42 will contact the lower endof the lever I! before the needle reaches the lead-off groove. The upperend of the lever l! is heavier than the lower end thereof'sothatnormally the lever rests against a stop on the cycle disc '20. Thisnormal position of the lever I1 is shown in Fig. 3a.

---In the samefigure, the tip of the strip 42 is disclosed in a positionpreceding contact between the strip 42 and lever l1. Eventually,however, during the play of the'record, the tip of the strip 42"wi11engage the lower end of the lever I! and cause'the same torotate aboutthe pin I8 in a counter-clockwise direction, as viewed 'in Figs.311-301." Thisraises the upper end of the lever 41 into the path oftravel of the pin l9 which, as will be remembered, rotates with theturntable.

" In'addition to the vertical side surface of the pin l9 heretoforedescribed, said pin has a sloping lower surface. The distance the tonearm moves forward during one revolution of said record in a play of thesame will move the strip 42 forward gen-ate only a short distanceinsufiicient to cause the upper end of the lever to contact theverticalside face of the pin [9. However, such movement er the tone armwill cause the upper end of the lever to be raised a distance such thatthe tip' of said upper end will be engaged by the sloping under surfaceof the pin. Such engagement between the pin and lever I! will rotate thelever I! in a clockwise direction, thus resetting the lever t! to theposition shown in Fig. 30. Such cockw'i'se rotation of said lever willbe transmitted to the strip 42, causing the same to rotate relative tothe fiat plate 393 in a direction away from the stop 44. The position ofthe strip 42- before it is pushed back is indicated in Fig. 3b, and theposi: tion of said strip after it hasb'een pushed back is shown in Fig.30. In Fig. 3c, the notation C an indicates the position of the strip 42after beingpushed back, while the notation B indicates the correspondingposition of said strip before it has been pushed back. It will beobserved that the" backward motion of the strip 42 is againstthefrictional engagement betweeh said strip" and the plate 393. If thisfriction force is too high, theresetting motion of the lever 32B will betrans mitted' to the tone arm and will urigroove the needle, causing itto repeat grooves. According y, said frictional engagement between thestrip 4 2 and the plate 39B should be made less than the force requiredto un roove the needle but large enough to cause rotation of the leverIT'into the path of the pin l9.

Such design may be accomplished by selecting the proper weight of strip42. Also, this d'esigr'i can be brought about by making the lever If!relatively light and the pivot 18 with at" little friction as possibe.It will now be" appreciated that as the pin l9 makes one rotation, sodoes" the record, and' hence,- the needle wi l advance one'groove pitchdistance at 'each rev0lution, caus ing the lever ll to rotate and raisethe upper end thereof a distance proportionate to the ad vance of theplaying needle. The height of thesloping portion of the pin I 9 is madegreaterthan this rise of the upper portionof the lever I'1, therebyenabling said sloping portion to reset the lever ll once each revolutionas lon as the needle is in the spiral' playing groove; that is;immediately before the pin l9 reaches the, lever ll, the relativeposition of the parts will be that shown in Fig. 3b, and as: the pin I 9leaves the lever ll, the relative position of the parts-will'be thatshown in Fig. 30. However, eventually, the needle will reach thelead-off groove. As is well known, the advance per revolution,- orpitch,- of a lead-off" groove is many times that of a recording groove.Therefore, as the needle traverses the'lead-off groove, it raises theupper end of thelever I? a distance greater proportionately than saidpin is raised during the ordinary ad-, Vance of the tone arm asinglepitch distance at such time as the record is playing. Thedistancethe upper end ofthe lever is raised is greater than'the heightof the inclined portion of the pin l9; This causessaid upper'endlto'contaet the vertical side surface of the pin I9 as shown in'Fig. 3d.Then, instead of the pin resettingth e lever I! by pushing the upper endthereof awn; the pin will force the lever l1 against the stop HA andstart the cycle disc rotating.

As already explained, the pin will maintain? contact with the upperendof. the lever 11, until the disc is turned far enough for therubbe'rltire 2| to engage the side surface of the disc. therubbertirecontiriues' to turn the disc' for one I sive record ma prevent s d;sa ,4

ger wh ich liesflin t path of travel of the strip iii retention un'riisaid tire (mesa-gain re-ehtrs the notch portio n 29A; Rotation of thedisc dur ing one revolution completes a record change cycle, depositinga new record on the turntable,

moving the tone arm out of the way of the deend of the lever ll riseswhenthe tone arm moves the pitch distance of a playing groove. How"ever; it will be understood that if said height is simply greater thanthe distance moved by the upper end of the lever I? for advance of theneedle one pitch distance, the invention will be carried out. e I e H vY It will now also be a parent that pursuant to this feature of theinvention; the mechanism for a sensing the end of a record play measuresthe advance of the tone a1 once for each IVQlllti'on of the turntable,-and immediately upon measuring if the end of the record hasnot beenreached, res'ets. It should also be noted that the l stoppin 4'4 andresetting pin 43 conjointly act to limit the outward moven'ieht of thetone armat such time as the same is moved; away from the central post 3becausepf engagementqf the cam 38' and follower 3'9: Thi si's necessarybecause: no

meanslijs' provided ea- 1 1 said feup er against the cam as the tonearmmoves outward, t is thus possiblethat the tonearm may be moving 4sition. However, this is d? by abutment of the strip 42 against theresetting pin 43 and abutment of the said Strip e at rs- It wilappreciated that the; foregoing means for sensing the endof eeojrd' playfunction only when the" toneLairin d "g one revolution moves" furtherthan the 7 a1 pitch distance. How; ever, some" reoords have a very smallIea'd fi groove and it is; desirable, therefore to provide in additionto: the abovedes'cribed pitch responend-sensing mechanism to include are se sing the" m re record play, which-latter means is responsivetothepo sition of the toneafrh'and which will; act in the event that thetonefarm moves'very close to the eentrar post 3* without ever-advancingmore than the normal pitch distahcduring any given revolution. suchposition sensing means includes a spring 45" (Figs. 1;; 8f and 8a)"which is secured to an e'dgeflof the flat plate: 393 remote from thespring has an upstanding firi- 42" as the 's'anie'turnsaboutthe' liftDinfi.

It will as understood"; that during orolih'a ry 0p e r'ation of thestrip 42 as the mechanism for measuring" the advanceof the tone arm onceduring each revol'ution or the turntable, said strip is caused" to'rotate in short angular steps in a counter-cloekwise direction; asviewedin Fig. 3', about the 11ft pin 34 untiis'uehtime as a marked advance ofthe tone arm will oaus'elthe lever I? tobe moved suffici'ehtly' toengage the; pin [9. Howev r, when the strip 42 is moved farenoughtoencounter the spring 45, said strip, instead of beingpushedback bytheresetting action of the IBonthe lever lll', will riesumeits position assoon as the pin IBJpasses the upper end of said lever, the spring d eserving to bias the strip 52 back. This causes successive advances ofthe tone arm during consecutive revolutions or the turntable to beadded, and therefore, in two or a few 11' revolutions, the lever will betilted sufiiciently for its upper end to engage the pin |9. In thismanner, records without lead-off grooves, or of very small centraldiameter, are tripped off at the end of a playing cycle.

It is also desired to point out that the determination of the advance ofthe tone arm during one revolution of the turntable is measured over asmall fraction of a revolution. This is highly desirable since itnullifies the effect of an eccentric mounting of the record. Sucheccentric mounting at the present time has caused considerabledifficulty in most trip mechanisms, as, for example, in velocity tripmechanisms, position trip mechanisms, and those trip mechanisms whichmeasure motion of the tone arm during a revolution. However, the presentpitch measuring trip mechanism determines the advance of the tone armand resets itself almost instantaneously at one definite position foreach revolution of the turntable, and, therefore, is not sensitive tothe wobble of the tone arm due to the eccentricity of the record spiralcenter with respect to the turntable center, which wobble occurs inphase with the rotation of the turntable.

The discriminating mechanism The discriminating or detecting mechanismis that which ascertains the size of a record and automatically inresponse thereto, positions the tone arm in the starting groove in arecord of the measured size. Attention is recalled to the manner inwhich the tone arm is moved back toward the central post 3. This motionis caused by engagement of the cam 38 with the spring portion 48 of thefollower 39. Such motion causes the tone arm to rotate in a clockwisedirection, as viewed in Fig. 8, and causes the plate 393 to rotate withthe tone arm inasmuch as the sam is fixed to the lift pin 34. However,this plate carries the projection 39A. When a record of minimumdiameter, for example, a -inch record, is lowered from the stack to theturntable, said record does not engage any element of the discriminatingmechanism. During theinward movement of the tone arm at the time such arecord is to be played, the clockwise motion of the flat plate 39B ischecked by abutment of the projection 39A against a dog 4|, pivoted tothe bracket 3|, as clearly shown in Fig. 2. The relative position of theprojection and dog at such time is illustrated in Figs. 8a and byposition 2 in Fig. 7. When a record of larger diameter is lowered to theturntable, an element of the discriminating mechanism is engaged andmoved by the record. This causes another dog to be disposed in the pathof travel of the projection 39A during inward movement of the tone arm.Said dog is disposed in advance of the dog 4|. Thus, inward movement ofthe tone arm will be halted at an earlier stage, and in such manner, alarger record, for example, a 12-inch record will cause the tone arm tobe initially positioned further away from the central post 3.

More specifically, said discriminating mechanism includes a lever 46v(Figs. 1, 4, 5, 6 and '7) which is pivoted on a pin 4'! (Fig. 2)rotatably mounted in fixed bearings in a bracket secured to the supportS. The lever 46 is unbalanced by a weight W fixed to an end thereofremote from the end facing the stack of records. This weight is of suchmagnitude and so located as to cause the lever to normally seek anapproximately horizontal position. When in such attitude, the

forward end of the lever, i. e., that remote from the weight, willproject into the path of a lowering record of larger diameter, e. g.,12-inch, but not into the path of a lowering record of smaller diameter,e. g., 10-inch. Said lever has a cam element 46A provided on its uppersurface. This cam element lies beneath the inturned upper end of afollower rod 48 so that said rod is supported on the cam element. At thebeginning of each cycle, the lever 46 and its follower 48 are disposedin the normal position, illustrated in Fig. '7. If a large discdescends, it will strike the forward end of the lever 46, rotating thesame to the position illustrated in Fig. 4. In this position, the camelement 46A presents a flat upper surface close to the pivot pin 41,whereas, as will be seen from inspection of Fig. 7, in the normalposition of the lever 46, the follower is supported by a part of the camelement relatively remote from the pivot pin 41. Thus, when the lever isrota.ed by the passage of a large disc, the follower 48 is lowered. Dueto the fact that the upper surface of the cam element in said positionis flat, the follower will hold the lever 46 in this new position.

The lower end of the follower 48 is positioned adjacent the dog 4| onthe side of the dog nearest the projection 39A, as will be seen in Figs.8 and 8a. When the follower 48 is lowered upon passage of a large disc,the lower end thereof will be interposed in the path of travel of theprojection 39A and thereby cause the tone arm to stop its inwardmovement at the lead-in groove of the large record.

The operation of the discriminating mechanism is as follows: Assumingsaid mechanism to be in normal position, as illustrate-d in Fig. '7,when a large disc drops, it will move the lever 46 and follower 48 tothe position illustrated in Fig. 4. At such time, the plate 393 is inelevated position on the plane illustrated by position I in said figure.Said projection is also angularly spaced from the dog 4| and lower endof the follower 48. The follower 39 is then moved in a direction toshift the tone arm inwardly by engagement therewith of the cam 38. Theprojection 39A on the plate 39B will strike the lower end of thefollower 48. Now, the tone arm will be vertically lowered and, at thesame time, the follower 39 depressed. This causes the same to be movedto position 2 in said figure so that the tone arm is free to swinginwardly while following the playing spiral of a record.

At the end of the play, the follower 39 will reach position 2 in Fig. 5at which time it is beneath the lower end of the follower 48 and beneaththe pivoted dog 4|. Now, the cycle disc has been placed in operationand, as will be remembered, the initial step is to raise the follower 39so as to elevate the tone arm. Raising the follower 39 elevates the dog4| and follower 48 but when the follower 48 is raised, the weight W willrestore the lever 46 to its horizontal position. The movement of thefollower 39 from depressed to raised position is illustrated bypositions and 2 of Fig. 6, the disposition of the parts in position 2being illustrated in full lines in said figure. This resets thediscriminating mechanism. Now, if a record of smaller diameter islowered, the raised follower 39 will encounter not the follower 48 butthe dog 4| during its movement from position I to position 2, asillustrated in Fig. 7.

Next, the follower 39 lowers, as shown in posi-i tion of said figure,whereupon the tone arm is free to swing inwardly. In the event that thereject button It is pressed while the tone arm is in raised position, inwhich case the flat plate 393 is not beneath the follower 48, saidfollower would not be reset. To provide for such contingency, a lever 49is included. This lever is pivotally mounted beneath the support S andis caused to rotate when the reject button is pressed. Said lever isconnected to the follower 48 and rotation thereof upon pressing thereject button will lift 48, allowing 46 to be reset.

It will thus be seen that there is provided an automatic phonograph inwhich the several objects of this invention are achieved, and which arewell adaptedto meet the conditions of practical use.

As various possible embodiments might be made of the above invention,and as various changes might be made in the embodiment above set forth,it is to be understood that all matter herein set forth or shown in theaccompanying drawings is to be interpreted as illustrative and not in alimiting sense.

Having thus described my invention. I claim as new and desire to secureby Letters Patent:

1. In combination, in an automatic phonograph including a turntable anda stationar central post about which said turntable is adapted torotate: means to support a stack of records on the central post offsetfrom the axis of rotation ,of the turntable, said mean including anelement for supporting the lowermost record of the stack adjacent itscentral opening, means to level the records in said stack, said leveling means including at least two elements diametrically disposed onopposite sides of the central post and adapted to press down against thetop surface of the uppermost record in the stack, said elements beingmounted for vertical movement, and means to maintain said elements in acommon plane as they move vertically, means to rotatably mount saidstack record levelling means about an axis parallel to the central postat a point remote from the central post whereby said levelling means maybe swung clear of the stack of records when records are loaded on orremoved from the central post, and means rotatable about said axi withsaid record stack levelling means and moved into operative position whensaid levelling means is rotated out of operative position to support theunder surface of the lowermost record of the stack adjacent theperiphery thereof.

2. In combination, in an automatic phonograph including a turntable anda stationary central post about which said turntable is adapted torotate: means to support a stack of records on the central post offsetfrom the axis of rotation of the turntable, said means including anelement for supporting the lowermost record of a stack adjacent itscentral opening, means to level the records in said stack, said levelingmeans including at least two elements mounted for vertical movement andcoordinated for joint movementin a common plane as they move vertically,means to mount said 'stack-record-leveling means for rotation about anaxis parallel to the post to one side of the stack whereby said levelingmeans may be swung clear of the stack of records when records are loadedon or removed from the central post, and means rotatable with saidrecordstack-leveling means and moved into operative position, when saidleveling means is rotated out of operative position, to support theunder sur- 14 face of the lowermost record of the stack adj acent theperiphery thereof.

I 3. In combination, in an automatic phonograph including a turntable, atone arm, a notched cycle disc and a rotary frictional member turned bysaid turntable and normally freely turning in the notch of said disc: arecord end play sensing means comprising an element frictionally coupledto said tone arm so as to move therewith and to be capable of movementrelative thereto, a second element pivoted on said cycle disc to turnabout a horizontal axis, said second element including an end having asubstantially horizontal side and a substantially vertical side, theother end of said disk being positioned for engagement by said firstelement in such manner that advance of said tone arm will cause thefirst-mentioned end of said second element to move toward said turn-.

table, a member carried by said turntable and having a sloping undersurface at an acute angle to the plane of rotation of the turntable anda vertical side above said under surface, said member being disposed sothat during rotation of the turntable said member will intersect theposition of the mentioned end of the second element, said slopingsurface being high enough to engage the horizontal side of thefirst-mentioned end of thesecond element to push down said end when thesame is raised at two successive revolutions of the turntable a distancenot substantially greater than that corresponding to an advance of thetone arm a pitch of the playing spiral of a record, the vertical side ofsaid member engaging the vertical side of the first-mentioned end of thesecond element when said end is raised up a distance corresponding to anadvance of the tone arm substantially more than the pitch of the playingspiral of a record, means to limit rotation of said second elementrelative to the disc when said second element is engaged by said memberso that said member will initiate rotation of the cycle disc when thesame engages the second element and move said disc substantially topermit 7 frictional engagement between the circular frictional memberand the cycle disc whereby said cycle disc, when the second element isengaged by the member carried by the turntable, will turn through onerevolution until the circular frictional member again reaches the notchin the cycle disc.

4. In combination, in an automatic phonograph including a turntable, atone arm, means to support a stack of records of difierent fixeddiameters and means to successively transfer records from said stack tosaid turntable: means to swing the tone arm out away from the center ofa played record and to then swing said arm back above the startinggroove of the next record, said means including an element movabletherewith, said element having a projection, means to shift said elementin a direction transverse to that in which it moves upon motion of thetone arm toward and away from the center of a record, a stop disposed inthe path of travel of said projection in one extreme position thereof asthe tone arm moves toward the center of the record whereby to rendersaid tone arm moving means ineffective to advance the tone arm furthertoward the center of a record, a second stop between said first stop andsaid projection when the tone arm is swung out, and means disposed inthe path of travel of a large record moving from the stack to theturntable, said means being operable upon engagement by a large recordto move the second stop in a direction parallel'to the direction inwhich said element shifts into the path of travel of the projectionwhereby, when a large record is to be played, the tone arm moving meanswill be rendered ineffective earlier in its advance toward including aturntable, a tone arm, means to support a stack of records of differentfixed diameters and means to successively transfer records from saidstack to said turntable: means to swing the tone arm out away from thecenter of a played record and to then swing said arm back above thestarting groove of the next record, said means including an elementmovable therewith, said element having a projection, means to shift saidelement in a direction transverse to that in which it moves upon motionof the tone arm toward and away from the center of a record, a stopdisposed in the path of travel of said projection in one extremeposition thereof as the tone arm moves toward the center of the recordwhereby to render said tone arm moving means ineffective to advance thetone arm further toward the center of a record, a second stop betweensaid first stop and said projection when the tone arm is swung out, andmeans disposed in the path of travel of a large record moving from thestack to the turntable, said means being operable upon engagement by alarge record to move the second stop in a direction parallel to thedirection in which said element shifts into the path of travel of theprojection whereby, when a large record is to be played, the tone armmoving means will be rendered ineffective earlier in its advance towardthe center of the record, said element shifting after play of a recordto its other extreme position in which as the tone arm is moved awayfrom the center of a record, the projection will clear both stops, saidtone arm moving means including a lost motion mechanism whereby saidmeans can be rendered ineffective even when continuously actuated.

6. In combination, in an automatic phonograph including a turntable anda stationary central post about which said turntable is adapted torotate: means to support a stack of records on the central post offsetfrom the axis of rotation of the turntable, said means including anelement for supporting the lowermost record of the stack adjacent itscentral opening, means to press down on the uppermost record in saidstack at a plurality of points in a common plane so as to level thestack, means to mount said levelling means for movement about an axisparallel to the post between two positions, in one of which saidlevelling means is disposed for effective operation and the other ofwhich said levelling means is clear of the stack, and means about saidaxis to support the under surface of the lowermost record of the stackat a point remote from the center thereof, said last named means beingrendered effective when said levelling means is clear of the stack.

7. In combination in an automatic phonograph including a turntable, atone arm, a

. 16 notched driven cycle disc and a rotary driving member turned bysaid turntable, adapted to drive said disc and normally freely turningin the notch of said disc: a record end play sen s-' ing meanscomprising an element frictionally coupled to said tone arm so as tomove therewith and to be capable of movement relative thereto, asec'ondelement pivoted on said cycle disc and engageable by said first elementin such manner that advance of said tone arm will rotate the secondelement and cause one end of said second element to move toward saidturntable, a member carried by said turntable, said member having twosurfaces, one said surface being disposed to tance not substantiallygreater than that corresponding to an advance of the tone arm a pitch ofthe playing spiral of a record, said second element being rotated atsuch time in a direction opposite to that in which it is rotated by thefirst element, the other said surface of said memher being disposed toengage the mentioned end of the second element when saidend is raised upa distance corresponding to an advance of the tone arm substantiallymore than the pitch of the playing spiral of a record at two successiverevolutions of the turntable, said second surface causing the secondelement to rotate in the same direction as that in which it is rotatedby the first element, and means to limit rotation of said second elementrelative to the disc in the direction '3 in which it is rotated by thefirst element, so that when said second element is engaged by the secondsurface of said member, said member and second element will initiaterotation of the cycle disc and move the disc substantially to permitengagement between the rotary driving member and the disc.

FRANK M. J OHNSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date I 1,271,590 Lefever July 9, 19181,474,776 Hunt Nov. 20, 1923 1,879,291 Johnson et al Sept. 27, 19322,090,746 Compare Aug. 24, 1937 2,211,423 Hokanson Aug. 13, 19402,237,340 Downs Apr. 8, 1941 2,270,995 Compare Jan. 27, 1942 2,286,490Knox June 16, 1942 2,287,727 Cranmer June 23, 1942 2,293,723 EricksonAug. 25, 1942 2,311,596 Pressley Feb. 16, 1943 2,328,052 Butler Aug. 31,1943 2,330,293 Knox Sept. 28, 1943 2,333,414 De Tar Nov. 2, 19432,371,362 Small Mar. 13, 1945 2,390,862 Alexandersson et al. Dec. 11,1945 2,402,150 Dale June 18, 1946 FOREIGN PATENTS Number Country Date99,762 Sweden Sept. 3, 1940

